Dry shavers

ABSTRACT

A dry shaver having a cutting foil of a cylinder surface configuration. In the interior of said cutting foil a reciprocable cutter head is arranged which is in driving connection with a motor that is also housed in said interior. Opposite said cutter head at least one biasing roller is arranged for urging said cutting foil in intimate contact with said cutter head. The motor has its shaft parallel to a generatrix of the surface of said cutting foil, and the shaft ends of the motor each carry a cam disc, each of which is cooperating with a coordinated reciprocable arm, which arms extend normally to the shaft of said motor and are coupled at their freely movable end to the cutter head.

United States Patent 1191 Cobarg 1 Sept. 9, 1975 1 DRY SHAVERS 3.037,2s1 6/1962 Arey 30/4314 [75] Inventor: Claus Christian Cobarg, Steinbach, FOREIGN PATENTS OR APPLICATIONS Germany 625,928 8/1961 Canada 311 4191 [73] Assignee: Braun Aktiengesellschaft, Frankfurt am Main. Germany Primary Examiner-Al Lawrence Smith [22] Filed: N0 lz, 1973 Assistant Examinerl 1obert C. Watson Attorney, Agent, or FzrmErnest F. Marmorek [21] Appl. No.: 414,767

[57] ABSTRACT 30 F Al't P"tDta I orelgn pp y a A dry shaver having a cutting foil of a cylinder surface Ausma Wig/72 configuration. In the interior of said cutting foil a re ciprocable cutter head is arranged which is in driving [52] 30/4331; 30/219 connection with a motor that is also housed in said in- [5 l] B26B 19/02 terior. Opposite said cutter head at least one biasing [58] held of Search 30/4391 roller is arranged for urging said cutting foil in inti- 30/42 34651 mate contact with said cutter head. The motor has its shaft parallel to a generatrix of the surface of said cut' {56] References cued ting foil, and the shaft ends of the motor each carry 21 UNITED STATES PATENTS cam disc, each of which is cooperating with a coordi 2,302,941 11/1942 Frey 30/4392 nated reciprocable arm, which arms extend normally 2318351 5/1943 Alexayu to the shaft of said motor and are coupled at their 2,363,849 H944 Bailey 1 1 1 1 1 30/4192 X freely movable end to the Cutter hflad 2,526,l53 10/]950 Page ,1 30/46 X 2,802,261 8/1957 Heyek 1. 30/4392 10 Claims, 2 Drawing Figures l [in %ll'l Ii 11/ ll/ ll/Il/ PATENTED 35F 1 1K "IIIIII lllllalilslil DRY SHAVERS BACKGROUND OF THE INVENTION The invention relates to a dry shaver of the kind which includes a cutting screen or foil for example of a cylindrical surface configuration, a reciprocable cutter head or shearing head coupled to a drive means and biasing rollers arranged opposite to the cutter head.

In a known dry shaver having the features set out above, movement of the cutter head is effected by means of a bent lever which is connected by a plurality of transmission parts to a drive motor. Such a construction requires a relatively large number of bearings and component parts and is bulky.

An object of the invention is the provision of a dry shaver of the above kind which is compactly designed, requires only a few components and is such as to permit counter balancing of the masses of the various moving parts.

SUMMARY OF THE INVENTION In accordance with the invention the drive means comprises a drive motor which is arranged in the interior or space within the cutting foil between the cutter head and the biasing rollers, its shaft being parallel to a generatrix of the surface of the cutting foil, the motor being fastened to a means carrying the biasing rollers. and two parallel and reciprocable arms being provided which extend normally to the shaft of the motor, each arm being coupled at one end to the cutter head, and a cam disc being positioned on the shaft, the disc being in contact with the associated reciprocable arm.

The energy of the drive motor is transferred by means of the cam disc directly to one of the reciprocable arms without additional components being necessary, The reciprocable arms also serve as a supporting device for the cutter head. The drive motor is housed in the space within the cutting foil, thus enabling a compact design.

The movable ends of the reciprocating arms may be connected to a rod or beam, to which the cutter head is coupled. Preferably, the drive motor is supported resiliently in an axial direction such as to obtain counter balancing of the masses of all moving parts of the dry shaver.

The novel features that are considered characteristic of this invention are set forth with particularity in the appended claims. The invention itself, however, both as to its organization and method of operation, as well as additional objects and advantages thereof, will best be understood from the following description when read in connection with the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is an axial sectional view of the main parts of a dry shaver according to the invention, and

FIG. 2 is a sectional view of the shaver in the direction of the arrows lI-II in FIG. 1 without the casing shown DESCRIPTION OF THE PREFERRED EMBODIMENTS The dry shaver includes a drive motor I which is fixed relative to the casing of thc shaver and is housed in the space within a cutting foil 2 which is of a cylindrical surface configuration. At either end of the shaft of the drive motor 2 cam disc 3 and 3a are pro- (ill vidcd, which have projecting cam formations which, in a side clcvational view, are shaped like a sine wave. On either side of the drive motor I reciprocating arms 4 and 5, respectively. are arranged, each of which is fixed at its one end to an arm of an L-shaped bracket or cantilever 6. The other ends of said arms 4 and 5, which reciprocate during operation, are connected to a rod or beam 7 which extends at right angles to said arms. Each of the reciprocating arms 4 and 5 adjacent cam disc 3 and 3a, respectively, is fitted with a stud 8 and 8a, respectively, made of a wear-resistant material and being in sliding contact with the coordinated cam disc.

A connecting pin 9 is fastened in the centre of beam 7 which pin is protruding towards the cutting foil and is surrounded by a compression spring 10. The connecting pin 9 engages in a recess provided in the body of a cutter head 11, resulting in coupling the cutter head for reciprocable movement to beam 7. The compression spring 10 is dimensioned to bias said cutter head 11 towards the cutting foil 2. Opposite to the cutter head and in the interior or space within the cutting foil 2, a roller 12 is provided which is supported in bearings by the casing and around which the foil is entrained. The roller 12 is provided with grooves 13 which prevent shaved beard-stubbles from blocking movement of the cutter head. The L-shaped bracket or cantilever 6 is mounted about a pivotal axis 14 on the casing of the dry shaver whereby the mass forces of the moving parts are counter-balanced.

The oscillating arms 4 and 5 are resilient parts, for example leaf springs, and are in intimate contact with cam disc 3 and 3a, respectively, to maintain associated stud 8 or 81:, respectively, in permanent contact with the associated cam disc.

In operation of the dry shaver, rotation of cam discs 3 and 30 brings about a sinusoidal motion of studs 8 and 8a, which impart this motion to the reciprocating arms 4 and 5, which in turn drive the beam 7 and the cutter head 11 coupled thereto, for a reciprocating movement.

Any other similarly operating transmission device may be employed instead of the cam discs. The drive shaft f.i. may be fitted with one instead of two cam discs. Instead of biasing roller 10, a plurality of biasing rollers in parallel arrangement may be provided, the axes of these being situated on a cylinder surface. In addition, the coupling between the cutter head and the reciprocating arms may be modified in various ways and the motor may be resiliently supported in an axial direction so as to counter-balance the masses of all moving parts of the dry shaver.

The cutting foil 2 is supported to be freely rotatable and maintained in an open loop, over the roller I2 and the cutter head II which are biased outwardly against the cutting foil 2 by the action of compression spring 10 as shown in FIG. 2. i.e. the foil functions as a movable endless belt which, during shaving, rides along the skin. Thus, a comfortable shave is achieved. The foil 2 is, however, prevented from movement in a direction ofthe axis of the motor drive shaft, i.e., it is constrained against transverse movements.

What is claimed is:

I. In a dry shaver,

in combination,

a first member including a rotatable, endless, flexible belt-type perforated cutting screen;

a second member including a shearing head positioned in operative contact with at least a portion of said screen;

suspending means operable for suspending the screen rotatably;

said suspending means comprising a roller means in cluding at least one roller and being operable. in combination with said second member, for maintaining said cutting screen in a circumferentially extended position by suspending the screen noncircularly; and

reciprocating means operable for reciprocably moving one of said members relative to the other a holding means;

said roller means being pivotally suspended from said holding means,

a casing;

said holding means including a cantilever operable for pivotally securing said holding means to said casing.

2. A dry shaver according to claim I, wherein said cantilever is pivotally attached to the casing at right angles to the shaft of the motor.

3. In a dry shaver,

in combination,

a rotatable, endless flexible cutting screen;

suspending means operable for suspending the screen rotatably;

a shearing head positioned in operative contact with at least a portion of said screen;

reciprocating means comprising a drive motor surrounded by said screen having a shaft the axis of which is substantially parallel to the axis of said screen and cam and cam follower means driven from said motor;

said cam follower being operably coupled to said shearing head whereby reciprocating motion is transmitted from said reciprocating means to said shearing head.

4. In a dry shaver as claimed in claim 3. said cam follower means including a first member comprising at least one reciprocable arm. and

a second member operably coupled to said reciprocable arm and to said shearing head whereby reciprocable motion of said arm will be transmitted to said second member. 5. In a dry shaver as claimed in claim 4, said first member comprising two substantially parallel recipro' cable arms each coupled to said second member and two cams each corresponding to one of said arms.

6. In a dry shaver as claimed in claim 4, wherein said second member further comprises a beam, said shearing head being coupled to said beam and said reciprocable arm being coupled to said beam.

7. A dry shaver according to claim 6, wherein the shearing head is coupled to said beam by means of a 

1. In a dry shaver, in combination, a first member including a rotatable, endless, flexible belttype perforated cutting screen; a second member including a shearing head positioned in operative contact with at least a portion of said screen; suspending means operable for suspending the screen rotatably; said suspending means comprising a roller means incluDing at least one roller and being operable, in combination with said second member, for maintaining said cutting screen in a circumferentially extended position by suspending the screen non-circularly; and reciprocating means operable for reciprocably moving one of said members relative to the other a holding means; said roller means being pivotally suspended from said holding means, a casing; said holding means including a cantilever operable for pivotally securing said holding means to said casing.
 2. A dry shaver according to claim 1, wherein said cantilever is pivotally attached to the casing at right angles to the shaft of the motor.
 3. In a dry shaver, in combination, a rotatable, endless, flexible cutting screen; suspending means operable for suspending the screen rotatably; a shearing head positioned in operative contact with at least a portion of said screen; reciprocating means comprising a drive motor surrounded by said screen having a shaft the axis of which is substantially parallel to the axis of said screen, and cam and cam follower means driven from said motor; said cam follower being operably coupled to said shearing head whereby reciprocating motion is transmitted from said reciprocating means to said shearing head.
 4. In a dry shaver as claimed in claim 3, said cam follower means including a first member comprising at least one reciprocable arm; and a second member operably coupled to said reciprocable arm and to said shearing head whereby reciprocable motion of said arm will be transmitted to said second member.
 5. In a dry shaver as claimed in claim 4, said first member comprising two substantially parallel reciprocable arms, each coupled to said second member, and two cams each corresponding to one of said arms.
 6. In a dry shaver as claimed in claim 4, wherein said second member further comprises a beam, said shearing head being coupled to said beam and said reciprocable arm being coupled to said beam.
 7. A dry shaver according to claim 6, wherein the shearing head is coupled to said beam by means of a compression spring.
 8. A dry shaver according to claim 3, wherein the cam follower is biased towards its respective cam.
 9. A dry shaver according to claim 3, wherein the drive motor is supported resiliently in an axial direction such as to counter-balance the masses of all moving parts of the dry shaver.
 10. A dry shaver according to claim 1, wherein the reciprocable arms are leaf springs. 